Improvement in lamps



UNrrEio; STATES ATENT rrrcn'.

RUFUS S. MERRILL, OF BOSTON, MASSACHUSETTS.

l M PROVE ME NT IN LAM PS.

To all whom it may concern:

Be itknown that I, RUFUS SPAULDING MER- RILL, of Boston, in the countyof Sufl'ollc and State of Massachusetts, have invented certain new anduseful Improvements in Lamps; and I hereby declare that the following isa full, clear, and exact description of the same.

My invention relates more particularly to the burners of lamps in whichfluid or certain products of the distillation of petroleum or coal-oilor other light hydrocarbon fluids are burned; and the object of myinvention is to render such lamps perfectly safe and increase theirilluminating power.

The danger attending the use of such light volatile hydrocarbon fluidshas several sources: first, the heat conveyed from the burner to the capof the lamp aiding the development of vapor, whose expansive force mayexceed the resistance of the fluid-vessel and result in its exploding 5second, the condensation of vapor or excess of fluid drawn up by thecapillary action of the wick at the tip of the burner causing it tooverflow and rendering the fluid thus collected around the base of theburner liable of being ignited.

These are the principal defects which it is proposed to be obviated bythese myimprovements, and they consist, first, in the method,hereinafter more fully explained, of insulating the wick-tube from themetallic cap; and, secondly, in the mode, hereinafter described, ofcollecting the overflow and condensed vapor at and around the burner,and of keeping the burner at a comparatively low temperature.

To enable others to make and use this my invention, I shall now proceedto describe the same, referring to the accompanying drawings, in which-Figure 1 is an elevation, partly in perspective, of my improved burner.Fig. 2 is a vertical section through the axis thereof; Fig. 3, anelevation of the wick-tube detached; and Fig. 4, a perspective view of amodification, in part, of the burner.

In the said drawings, E is the cap of the fluidvessel or base of theburner. As usual, it is provided with an annular screw-threaded flange,whereby it is secured to the metallic collar cemented to thefluid-vessel.

I11 most burners heretofore constructed the wick-tube is directlyattached to the cap. This is generally effected by soldering. Theobjection to this mode of construction is twofold: First, the heat ofthe flame is conveyed from the tip of the burner to the cap and,secondly, the solder 'is often melted by the heat thus transmitted or bythe overflowing burnin g-fluid igniting in the immediate vioinityofthesolder.

To remedy this I insulate the wick-tube in the manner as follows: Ileave a central opening in the cap, through which the wick-tube B passeswithout touching the sides of said openin g and projecting a shortdistance below into the vessel. From the cap plate risesa concentriccylindrical socket, A, within which the lower half of the wick-tube isheld by being embedded in plaster ofparis, M, or other suitable plasticand cementing non-con ductor of heat. To prevent the wick-tube, which isslightly tapering from the base to the tip, from slipping down into orfrom being drawn out of the reservoir, I provide the tube wit-h anannular flange, G, made in preference in the shape of an inverted cup,care being taken. first, to interpose some plaster-of-paris or otherlike substance between the internal parts of the cap and the edges ofthe cup flange.

For the better appreciation of the second part of my invention, I wouldobserve that the fluids now mostly sought to be used as a burnin g-fluidare the products of the distillation or refining of the petroleum-oils,and whichare hydrocarbons of a highly-inflammable character, so thattheir use in ordinary lamps is attended with much danger. Having beforeexplained their causes or sources, I would further observe that toremove these various improvements have been suggested and used, but

none to my knowledge appear to have answered the purpose. Thus theinsulating the tip of the burner, although preventing the heat of theflame from being transmitted to the cap of the burner, does not preventthe condensation of the vapor and the overflowing of the fluid and thedangers accompanying the same. ()n the other hand, devices producingcurrents or injets of air along the wick-tube were applied for thepurpose of keeping the tube cool; but by this means the condensation wasonly accelerated and the flow of the fluid down the tube by no meansstopped. Other devices similar in character have been adapted to burnerswith no better success. The object of the second part of my inventiontherefore is to effectually remedy these defects, and I haveaccomplished it by the construction of a burner attachment, as follows:

With a centrallyperforated disk, 0, having an upper flange 011 theoutside periphery and an under flange on the inner periphery, I combineone or two concentric cones, O and D, of a pitch equal to that of thewick-tube, under such an arrangement as to leave annular spaces orchambers equal in width, but closed at the bottom, around the wick-tubeand flush with the tip thereof. In making this attachment I preferentirely to dispense with solder. 'Each of the three pieces composing itmay be struck up in the manner well known.

I have here shown the lower disk to consist of a thin plate struck up soas to form the outer and inner flanges, while the cone 0 is shown struckup with a horizontal flange, bracing it against the outer flange of thedisk 0, and the cone D made without flange and held in place by theouter flange of the disk 0 project ing above the flange ot' the cone C;but the disk may be made with grooves and the cones may shut into thegrooves, so as to form a .tightjoint therein. These cone attachmentswhen slipped onto the wick-tube will be securely held in place withoutsolder, which presents the additional advantage of being easily removedfor the purpose of cleaning the lamp or trimming the wick.

From the foregoing it willbe understood that the excess fluid drawn upby the capillary action of the wick and the condensed vapors will becollected in the chambers, and there, by abstracting the heat of theburner, cool the inclosed wick-tube and become revaporized to supply theflame.

The second annular chamber has for its oflice to maintain an equabletemperature in the first chamber and to heat the outer air be forestriking the flame; but the latter chamber may be dispensed with.

Having thus described my invention, and the manner in which the same isor may be carried into effect, I claim l. The method herein described ofinsulating the wick-tube from the cap of the vessel by the interpositionof a non-conductor of heat, in the manner and for the purpose set forth.

2. The combination, with a cap provided with a socket to contain theinsulating cement ing substance, of the wick-tube provided with anannular plate to prevent its being moved within the cementing matter.

3. As an attachment to and in combination with the wick-tube, annularchambers or reservoirs arranged in the manner and for operation asdescribed.

In testimony whereof I have signed my name to this specification beforetwo subscribing witnesses.

RUFUS S. MERRILL.

\Vitncsses:

JACOB SANBORN MERRILL, THEODORE M. PLIMPTON.

